I have been using SQL for a couple of years now, primarily to write views / stored procedures for Crystal Reports. I am looking for some advice regarding the summing of values in a select that references multiple tables.

For example... 1. A call is logged (Calls table)2. Labour events are recorded against the call (Call_Events table)3. Parts are issued to the call

I need to return...1.The Call_Ref from the Calls table2.The sum of Event_Cost from Call_Events3.The sum of Cost_Price from Call_Parts_Used

Thanks very much for your alternative examples, however, my SQL returns the same result set as all your examples (where left join is used) so what I would like to know now is which solution is the best and why?